Mesalamine, 5-aminosalicylic acid, belongs to the class of anti-inflammatory agents and is used for the treatment of mild to moderate active ulcerative colitis.
Mesalamine is commercially available in various dosage forms such as Asacol® (mesalamine 200 mg and 400 mg delayed-release tablets; Procter and Gamble, USA), Asacol® HD (mesalamine 800 mg delayed-release tablets; Procter and Gamble, USA), Pentasa® (mesalamine 400 mg extended-release capsules; Shire, USA) and Lialda® (mesalamine 1.2 g delayed release tablets; Shire, USA) for oral administration. It is also commercially available for rectal administration as an aqueous suspension or as suppositories. Of all the dosage forms available, Lialda® is the only once-a-day dosage form of mesalamine available for induction of remission in patients with ulcerative colitis.
U.S. Pat. No. 5,541,171 discloses delayed release tablets comprising mesalamine coated with a layer of an anionic copolymer of methacrylic acid which is insoluble in gastric juice and intestinal juice below pH 7 but soluble in colonic intestinal juice in sufficient amount such that the dosage form remains intact until it reaches the colon.
U.S. Pat. No. 5,716,648 discloses an oral composition that relies on pH dependent soluble coating, but also includes a pH dependent alkaline material to attempt to compensate for patients with “subnormal intestinal pH”.
U.S. Pat. No. 6,773,720 discloses controlled release oral pharmaceutical compositions comprising an inner lipophilic matrix in which mesalamine is partly globulated and an outer hydrophilic matrix in which the lipophilic matrix is dispersed.
U.S. Pat. No. 5,171,580 discloses a formulation which includes a core coated with three different layers: an inner layer including an anionic polymer, an outer gastro-resistant layer and intermediate swellable layer constituted by high viscosity cellulose derivatives of high molecular weight.
U.S. Patent Application No. 2009/0028944 discloses a controlled release composition comprising mesalamine particles wherein the particles are granulated with a hydrophobic polymer and further embedded in a hydrophilic matrix.
We have now developed an alternative delayed release pharmaceutical composition of mesalamine.